Washing machine



Sept. 29, 1953 T. R. SMITH 2,653,433

WASHING MACHINE Original Filed Dec. 20, 1948 v '2 Sheets-Sheet 2 IN V EN TOR.

Patented Sept. 29, 1953 WASHING MACHINE Thomas R. Smith, Newton, Iowa, assignor to The Maytag Company, Newton, Iowa, a corporation of Delaware Original application December 20, 1948, SerialNo. 66,229. Divided and this application, October 17, 1950, Serial No. 190,518

Claims. 1

' The present invention relates to washing machines, and more particularly to washing machines of the type in which a washing operation is accomplished by agitating the liquid and material contained therein and in which the tub is thereafter rotated to extract the liquid from the material to eifect a partial drying thereof.

This application is a division of the parentapplication Serial No. 66,229, filed December 20, 1948', for a. Washing Machine. One object within the purview of the present invention is to provide novel means for controlling the driving relation between the motor for the washing machine and the rotating tub assembly, whereby the motor is protected against overloading during the spinning or extracting operation.

Another object is to provide in a washing ma.- chine a reversible driving arrangement whereby the motor operates in one direction for driving the agitators for washing and in the opposite direction for spinning the tub for extracting liquid from the washed clothes, the motor being flexibly mounted to prevent excess loads. thereon.

Another object is to provide a simple, novel and efiicient driving and transmission arrangement for washing machines wherein a smooth operation is maintained to meet the requirements for successful use Other objects, features, capabilities and advantages are comprehended by the invention, as will, later appear and as are inherently possessed thereby.

Referring to the drawings;

Figure l is a vertical cross-sectional view of an automatic washing machine embodying, the present invention;

Figure 2 is a horizontal cross-sectional View taken substantially in the plane represented by lines 2-2 of Figure 1 of the drawings. Referring now more in detail to the; drawings, an. embodiment selected to illustrate the com.- bined Washing and drying machine for washing, rinsing and spin drying fabrics and the like, generally comprisesv an outer casing or cabinet 2; for completely enclosing the various parts of: the: washing machine, and which is supported upon a base structure 4 which also serves to support an outer. stationary tub 6,. an inner tub Hi rotatably mounted therein, and power operated means generally referred to as 8 forthe washer.

The casing or cabinet 2 formed of a plurality of parts made from sheet metal, one of said parts being fabricated from a. single sheet v of metal. to provide oppositely disposed sidewall panels 12 and l d and a back wall panel I3, said panels being provided with an inturned horizontally flanged portion 20 along their upper edge, and the said panels i2 and Hi at the forward marginal edges remote from the back panel being provided with interned oppositely disposed vertically extending flanges 22 and 2 5. These flanges Z2. and 24 are adapted to mate with and be rigidly secured to similar vertical flanged par-- tions provided on opposite sides of a curved front panel 28.. This front panel is also provided with an upper horizontally disposed inturned flange 2t disposed in the plane of the horizontal flanges 20- on the side and the back wall panels. The lower portion of the front panel terminates with an inwardly extending flanged portion 3?" above the lower edge of the side and back wall panels to provide a toe space for the operator; A separate cover or foot board 32 is secured to the base assembly; Disposed. above the iii-tinned horizontal flanged portions is a horizontal. relatively flat cover or top 36, preferably formed from a single piece of metal and having vertically ex-' tending side portions 3'8 terminating in the inturned. horizontal flanged portions 40: at the lowor thereof which mate with. the flanged portions i8v and 28', the same being fastened thereto inv any desired manner;

' The top wall or cover 36 is formed with a contrally located access opening defined by a downwardly and inwardly extending flange ce to per access to the inner receptacle or tub Id This opening is normally closed by the lid or: door 42 hinged by the U-shaped. member 44 at one end thereof. by means of. horizontally disposed: hinge pins 4b mounted spaced brackets is on. the under side: of the cover or top wall 3% This lid swings upwardly to a substantially vertical position and. is: provided with a handle or grip- .it' at the end. opposite thehi-nge 44 to provide means for raising or lowering the: lid;

The bottom II! of the stationary tub o is formed with a centrally disposed opening defined by the up-standing. annular flange: I54 to which is: secured. stand-pipe [56 in the form. of an up standing sleeve or tubular shaped member. The sleeve [.56 projectsdownwardly below the bottom of the tub, as ati-5-8:,. and extends upwardly above said bottom and terminates in an: enlarged cylin drical portion Hill. This up-standing sleeve provides 'means through concentrically arranged shafts I62 and Hit extend; these: shafts being driven to actuate the agitators. i665 and i 58 and for rotating the inner: tub or receptacle lie. up-standingisieeve I556 is from the concentrically arranged shafts to permit lateral and gyratory movement thereof. The central portion of the tank bottom I21 adjacent to and outwardly of the annular flange I54 is provided with a spherical surface I'Ill for a purpose to be hereinafter more fully disclosed.

The inner rotary tub or receptacle II] is disposed within the upper portion of the stationary tub 6 and is spaced from the side walls thereof a sufiicient distance to permit of a certain amount of lateral or gyratory movement thereof without contacting the same. The said inner tub is in the general form of a truncated spherical hollow body member terminating in a horizontal plane at its upper marginal edge to provide an access opening I12 which is in alignment with the opening in the cabinet formed by the flange 4!] whereby the interior thereof is accessible to the operator. This hollow body member is provided with a substantially horizontally disposed bottom wall I14 opposite the opening I12.

The upper and lower portions of the receptacle II! are formed with mating hub portions which extend outwardly and in opposed relation to one another to provide the horizontally aligned hubs I76 and H8 which are adapted to receive the stub shafts I80 and I82 secured therein by means of pins or the like I84, upon which the agitators I65 and I68, respectively, are mounted for rotation about a horizontal axis. The tub I is further provided with the oppositely disposed offset portions 204 and 2% to accommodate the agitators I66 and I68, respectively, and the driving mechanism therefor, and in the side wall of which is formed a plurality of relatively large openings I86, each of which has its lower marginal edge disposed slightly above the horizontal axes of the stub shafts I32 and I82 which define a maximum liquid level for liquid within the tub IG and serve to permit the washing liquid to flow therethrough when the level thereof tends to rise above the plane of the lower marginal edges of these openings and also when the tub is rotated about its vertical axis.

The bottom wall I14 of the tub IE! is provided with an integrally formed housing structure I83 concentrically arranged with respect to the vertical axis of the receptacle I ll and having an annular and outwardly extending flange i353 seating upon, and being secured as by bolts or the like, to the outwardly disposed flange I92 of the hub member 994 which is secured to the outer hollow shaft 64 through the medium of pins I96, or any other suitable connecting means. The hollow rotatable shaft I64 extends downwardly through the opening provided in the sleeve member I56 of the outer tub 6 and is formed at its lower end with a reduced portion I98, having a shoulder 2G6 engaging a combined radial and thrust hearing assembly I636, whereby the inner tub is supported axially solely by this bearing, the said combined radial and thrust bearing assembly serving as a pivot point about which the said tub IE3 is rotated, as will be explained more fully hereinafter. The bottom of the tub Iii adjacent the central axis of the same, and immediately above housing I88, is provided with a raised or crowned surface 202 for accommodating certain driving mechanism disposed within the said housing I88.

The agitators I66 and I68 are of similar construction and each comprises a substantially spherical shaped base or disk portion 208 fitting within the offset portions 264 and 206, respectively, to provide a substantially. uninterrupted 4 inner surface for tub Ill. The agitators are removably secured to shafts I80 and I82 by means of the spring retaining rings 2H! fitting within complementary annular grooves formed in the shafts E86 and I82 and the hubs 2I2 and 2I4 of the agitators I66 and I68, respectively. The disk portions 288 of the agitators are provided with a plurality of openings 2I6 which extend "therethrough so that water or washing liquid may flow through such openings to the openings I and into the outer tub 5. Each of the agitators is preferably provided with a single vane, as illustrated, which extends vertically outwardly from the base and extends substantially across the entire width of said base. These vanes, when the agitators are mounted within the receptacle It, project toward the center of the inner tub is and the same are capable of agitating the liquid disposed within the tub or container when the same are rotated.

The inner shaft I62 is journalled in the outer sleeve I64 with its upper and lower portions in the bearings 2I8 and 229, respectively, and extends upwardly beyond the flange I92 and into the housing I83, the upper end thereof having the bevel pinion 222 secured thereto. The bevel gear 222 is mounted on the upper surface of the outer shaft IE4 through the thrust bearing 224, which prevents the inner shaft I62 from moving in a downward vertical direction, and to position the same with respect to the hollow shaft I64. The bevel pinion 222 meshes with the bevel gears 226 and 228 mounted adjacent the inner ends of drive shafts 23c and 232, respectively, which extend outwardly and horizontally in opposed relation and are journalled adjacent their inner ends in the inner bearings 234 and 235 formed in the housing I38 and adiacent their outer ends in the bearings 228 and 249. The bearings 238 and 242 are provided in the recess housings 242 and 244 disposed adjacent to and immediately below the agitators I65 and IE8, respectively. Mounted on the drive shafts 230 and 232 adjacent their outer ends are spur pinions 246 and 248 disposed within housings 242 and 244, respectively, which mesh with spur gears 250 and 252 of relatively large diameter, which may be integrally formed with the agitators I66 and I68, respectively, or formed separately and connected thereto. It will be seen from the drawings, that as the drive shaft I62 is rotated in any given direction that the bevel gear 222 connected thereto will rotate the bevel gears 226 and 228 in opposite directions for driving the shafts 230 and 232 and the agitators I66 and IE8 operatively connected in driving relation thereto, in opposite directions. Due to the opposite rotation of the agitators, the liquid or cleaning fluid within the receptacle I8 is forced from one side or face of one of the agitators to the oppositely facing side of the other agitator and is forced downwardly and over to the other side of the face thereon and is discharged therefrom and is then caused to flow back to the adjacent face of the first agitator by the second agitator. The opposite rotation of the agitators causes the liquid to flow in a continuous direction in a horizontally circular manner between the agitators and in a vertical semi-circular manner at and adjacent the agitators. The flow, however, will be very turbulent as the body of liquid is moved in the general direction indicated.

The housings 242 and 244 are each in comrnunication with the interior of the tub by way of channels, such as 254, and the openings 2I6 5. in the agitators. Laterally and on both sides of shafts 230 and 232, the housings. M2 and 244, respectively, are formed with radially extending portions 266 connected to the bottom wall I14 of the inner tub to provide passageways communicating at one end with the recesses formed by the housings 2G2 and 24 i and at the other end with the interior of the inner tub I through openings 268 provided in the bottom wall I'M.

Each of the housings 242 and 24.4 is provided with an opening exteriorly of the tub Iil which is closed by a wall element 256 connected to the tub III in any desired manner. The wall is apertured, as at 258, to permit water or cleaning fluid to be discharged from the tub I30 when the same is rapidly rotated in the washing cycle. The opening 258 is normally closed by a valve member 260, spring pressed into such position by means of the spring member 262 which permits the valve member 260 to be opened against the action of the spring during relatively high speed of the tub Ill. The outward movement of the valve members 260 is limited by stop elements 264 connected to the tub ID in any desired manner.

The primary object of the valves 2% is to provide means for flushing dirt and other foreign matter away from the inions and gears, which may have collected during the washing cycle in the recesses formed by the housings 242 and 244. Water or cleaning fluid for this flushing operation passes from the interior of the tub I0 outwardly through openings 2 I 6 in the agitators and channels 254 and through the openings 268 into the recesses formed by the housings 242 and 244.

As previously pointed out, the hollow shaft Hi l is formed with a reduced portion I93 providing the shoulder 200 which is in operative association with the radial and thrust bearing assembly generally referred to by the reference numeral I05. More particularly, the said shoulder 200 engages the inner race-ring 210 of the bearing Iilli to support the shaft I64 in vertical position. The outer race ring 272 is mounted in and connected to an annular member 214, S-shaped in vertical crosssection, the same being provided with a lower inturned flange 216 for supporting the outer race ring 212 and with an upper outwardly disposed flange 218 which overlaps and engages an annular shaped rubber bushing 280! This bushing, which may be of any desired resilient material, is positioned by an annular dish shaped retaining member 282 which has an inwardly disposed flange'284 on which the annular resilient bushing 280 is mounted and an upper and outwardly ex! tending flange 285 which is disposed within the opening we of the channel member Hi2 and overlaps the same and is rigidly connected thereto in any desired manner.

The inner drive shaft I62 extends downwardly through the hollow shaft I64 and is journalled in the bearings 2 I8 and 220 as previously indicated to prevent relative radial movement between these drive elements. The extreme lower end of the shaft I62 projects downwardly beyond the restricted portion 658 of the hollow shaft I64 and has a driving pulley or wheel 2B8 keyed or otherwise secured thereto in any suitable manner, whereby the same is adapted to drive the shaft I62. It is to be noted that the reduced end portion I98 is'disposed to have its end in abutting relation to the hub of the pulley 288 so as to prevent relative axial movement of the two shafts I62 and I64.

From the foregoing it will be seen that the combined radial and thrust bearing I06 not only supports the receptacle I0 but, through the thrust bearing 224 disposed between the bevel pinion 222 and the supporting hub member I94, maintains the pulley 288 in its proper operative position. As the receptacle, I0 is caused to move laterally within the stationary tub 6 during the spinning operation, or if the same is moved in any manner away from its vertical position, the receptacle ill will tilt about the bearing assembly I08, it being noted that the bearings constitute the sole support for the receptacle It and the agitators, and their operating mechanism. The pulley 288 is dish-shaped in such a manner that the horizontal plane defining the center of the groove for the driving belt 298 fitting therein, extends thro gh the pivot point of the bearing assembly are. in order to minimize deflection of the driving belt.

In order to maintain the receptacle II) in substantially its vertical position, there is provided a combined stabilizing and damper mechanism, generally referred to as 292, which is disposed immediately below the bottom I2! of the stationary tub 6. This mechanism includes a hollow sleeve-like member 294 surrounding the hollow shaft I64 which is provided with two radial bearings 296 and 298 journalled upon the hollow shaft ifid adjacent the upper and lower end portions of the tubular member 29 1. The upper end of the central tubular member 294 is formed with a spherical shaped wall 3% reinforced by a plurality of downwardly extending webs or brackets 39:. which provides a spherical shaped friction surface. lhe spherical shaped wall 30!) is adapted to contact a spherical shaped member 36% formed of friction material which is mounted upon the lower wall I2? adjacent the spherical shaped portion I'Eii through an annular tubular member 3538 which surrounds the downwardly extending end portion I58 of the sleeve I55. The hollow tubular member is preferably formed of some resilient material, the same being adapted to engage an annular shoulder 3638 provided adjacent the inner marginal edge of the member 304. Adjacent the lower end of each of the webs or brackets 392, four being provided in the illustrative embodiment of the invention herein described, there is provided an opening engaged by one end of a coil spring 3H9, which has its other end connected to the stationary tub 6 by means of a bracket 3H2 connected to the bottom wall I2? thereof. These springs are uniformly spaced around the member 294 so that springs of each pair are disposed in opposite relation to one another and due to' the angular position of these springs with respect to the tub and the connection at. the lower end of the webs 302, a component of the spring force is applied in a vertical direction to the friction member 3134. Since each spring is equally loaded and opposed by an oppositely disposed spring, the tub Ill will be maintained in its vertical position under normal conditions. Should the receptacle II) tend to move away from the vertical, the spring forces acting through the member 294 will tend to return it to its neutral or vertical position where the spring forces are all equal and opposite. As will be apparent, the surface of the spherical wall 308 is forced by the springs 3H1 toward the friction member 363 and, as the tub tends to move in a horizontal plane, a certain portion of the energy tending to move the tub is absorbed by the friction member. This friction member, therefore, tends to reduce the amplitude or extent of horizontal movement of the tub and absorbs some of the energy applied thereto.

Disposed about the outer periphery at the upper portion of the tub i is an annular or circular hollow tubular balancing member or ring 314 mounted in spaced relation to the receptacle upon a plurality of lugs 3l6 which are formed integrally with the tub and held in position by clamps 5 it which grip the ring and are bolted to the lugs. The inner hollow ortion of the balancing ring is packed with steel wool or other material to provide a large amount of exposed area for restricting and retarding to a certain degree the movement of a balancing fluid therein which partially fills the ring.

The driving means for the pulley 288 comprises a reversible motor 320 vertically mounted in, and supported by a frame 322 pivoted to the stationary bracket 326 connected to the vertical supporting element Hit of the base structure 4 for movement about a vertical shaft or axis 323 in remote relation to the axis of the motor. A drive pulley 328 having a V-shaped peripheral groove is connected to the rotor shaft of the motor and is adapted to drive the pulley 283 through the belt 233. The belt 290 is maintained under its proper belt tension by means of a horizontally disposed pro-loaded spring 336 connected at one end to the housing 322 and at its other end to the bracket 332 secured to the base assembly a, said spring acting to move the motor and its supporting frame 322 about its vertical supporting axis 324 in a direction away from the driven .pulley 288.

In bringing the tub iii and. its contents up to spinning speeds, a motor of the size which it is desirable to use in a washing machine of the type herein disclosed, will not attain its operating speed fast enough to prevent the starting winding thereof from burning out. In order to eliminate this difficulty, the motor 326 is pivotally mounted as described and operates in a counterclockwise direction, as disclosed in Figure 2 of the drawings, to spin the tub I!) and in a clockwise direction to rotate the agitators 568 and I68. The pivot 32% is arranged with respect to the motor so that the reactive torque of the motor operates against the spring 339 which holds the belt 296 tight so that the belt is loosened during the rotation of the motor in a counter-clockwise direction sumciently to allow the motor pulley 323 to slip on the belt 290. The spring 336 is adjusted so that the motor pulley will slip on the drive belt at a value considered to be the maximum safe output torque of the motor. In the operation of the washing machine, as soon as the motor is rotated in a counterclockwise direction, as viewed in Figure 2 of the drawings, the same immediately comes up to speed and slips on the belt 238 and provides a maximum safe torque which gradually accelerates the pulley 288 and the structure which is to be rapidly rotated thereby, including the tub iii and the contents thereof. When the motor is rotated in the reverse direction for operating the agitators, it is evident that the torque required to cause slipping is much greater as the pulley tends to move up on the side of the belt which is closer to the pivot point 32:3 and, accordingly, there is less leverage tending to move the frame structure 322 against the action of spring 339. With this arrangement, slipping of the motor can be provided for spinning the tub it in one direction and ample torque is provided for operating the agitators without danger of belt slippage in the reverse direction. When the motor 320 is operated to spin the tub Iii there will be a tendency under some conditions for the motor to hunt or oscillate about the pivot point 324. In order to prevent this oscillation or hunting of the motor a friction damper is provided. This friction damper comprises a leaf spring 334 connected to the motor housing at one end thereof and being provided at its other end with a transverse groove adapted to hold the friction member 333 therein and against the inside face of the angle iron HG upon which the motor is pivotally supported.

Rigidly secured to brackets 332 and 338 of the base assembly, and disposed between the drive and driven pulleys 328 and 288,is a reversible pump 340 capable of operating in either direction of rotation of the motor 320 for pumping liquid from the tub 6 either through a conduit 342 to drain, or through a conduit 344 back to the receptacle H] for recirculation.

The piping, directions of flow of water and the ump structure form no part of the present invention and accordingly will not be further described.

The pulley 354 is formed with a V-shaped annular peripheral groove adapted to receive a belt 356 which is driven by pulley 358 fixed to the drive shaft of the motor 320. The control of the flow of liquid either for recirculation through the conduit 344 or to drain through the conduit 332 is effected by any suitable valve mechanism.

Mounted on the inner side of the hub of the driving pulley 288 is a one-way clutch 384 comprising a body portion having tapered slots therein which have their openings disposed adjacent the reduced end portion I98 of the hollow shaft i54. A plurality of rollers are disposed in these slots so that when the driving pulley 288 is rotated in a clockwise direction, as viewed in Figure 2 of the drawings, as, for example, when the agitators I66 and IE8 are being operated, the rollers will be disposed in the larger part of the slots and, accordingly, no turning movement is applied to the hollow shaft ltd upon rotation of the pulley 283. At this time the pulley 288 which is connected to the shaft I62 causes rotation thereof for operating the said agitators. When the direction of rotation of the pulley 288 is reversed, however, the rollers move along the tapered slots and grip the hollow shaft 164 to eifect a driving connection between the pulley 288 and said hollow shaft IE4. It Will be apparent that during this operation the inner and outer shafts Hi2 and Hi l are rotated together in the same direction, and at the same speed, and inasmuch as there is no relative movement therebetween, the agitators I68 and 958 are maintained stationary with respect to their axes of rotation but the same will be revolved about the vertical axis of the tub it.

During the rotation of the inner shaft I62, when the agitators H55 and it?) are rotated for a washing operation, there is a natural tendency for the receptacle it to rotate with the inner shaft 32 which, if permitted, would reduce the eifectiveness of the washing action of the agitators. In order to maintain the tub is stationary during the washing operation there is provided a one-way clutch 386 mounted in the lower end of member 29:1 of the stabilizing and damper mechanism 292 which is adapted to hold the tub is and to prevent its rotation. This one-way clutch is similar to the one-Way clutch 384, except that the tapered slots formed in the body portion are disposed oppositely to the tapered slots in the one-way clutch 384. When the shaft I62 is rotated to rotate the agitators, the rollers 9 of this. one-way clutch 386 are positioned to grip the hollow shaft I64 and, inasmuch as the stabilizing and damper mechanism 292 is connected to the stationary tub 6 through the springs'3lil, rotation of the hollow shaft I54 cannot occur. When the rotation of the driving pulley i in the reverse direction and the one-way clutch 3'34 grips the outer hollow shaft ted to cause the tub It to rotate about its vertical axis, the one-way clutch 386 is released.

In a washing and drying machine of the type herein disclosed it is desirable to provide means for automatically operating the same. Such is fully described in the above identified parent application and is not being claimed in this divisional application. It might be stated however that the washing and drying machine above described is automatically operated through a complete cycle without its being necessary for the operator to do anything other than to adjust the control knobs prior to the time that the machine is set in operation.

In accordance with the contemplated operation of the washing and drying machine, the operator opens the lid 42 and places the clothes or fabrics to be washed in the receptacle ID. A proper quantity of a detergent is then poured into the receptacle, after which the lid is closed and then dependent upon the setting the machine is operated in a predetermined sequence.

In connection with the operation of the agitators I66 and I68 for washing and the spinning of the tub 10 for extracting liquid from the clothes or fabrics the reversible motor 320 is provided. The motor is pivotally supported on a vertical axis 324 in a manner whereby the motor pulley 328 is adapted to move toward the operatively associated pulley 288 to permit said motor pulley to slip with respect to the belt when the load upon the motor exceeds a predetermined value. The spring 338 is provided to urge the motor pulley into driving relation with the belt 290 and as stated, it is yieldable when the load exceeds said predetermined value. Also there is provided the friction member 336 engageable with a support to prevent oscillation of the motor 320 about its pivotal support 824 when the mot-or pulley slips with respect to belt 298.

While I have herein described and by the drawings shown an illustrative embodiment of the invention, it is to be understood that the invention is not limited thereto but may comprehend other constructions, arrangements of parts, details and features without departing from the spirit of the invention.

What is claimed is:

1. In combination, a support, a reversible motor having a drive pulley, means driven by said motor includin a driven pulley, a belt drive between said pulleys, means for pivotally supporting said motor upon said support for movement about a vertical axis to provide a positive driving relation between said drive pulley and belt in one direction of rotation of said motor and to provide for movement of said motor pulley toward said driven pulley to permit said motor pulley to slip with respect to said belt drive upon rotation of said motor in the other direction when the load upon said motor exceeds a predetermined value, means for urging said motor pulley into driving relation with said belt drive, said means being yieldable when said load exceeds said predetermined value, and spring means connected to said motor and having a friction member engageable with said support to prevent oscillation of said motor 10 about the pivotal support when the motor pulley slips with respect to said belt drive.

2. In combination, a support, a reversible motor having a drive pulley, means driven by said motor including a driven pulley, a belt drive between said pulleys, means for pivotally supporting said motor upon said support for movement about a vertical axis to provide a positive driving relation between said drive pulley and belt in one direction of rotation of said motor and to provide for movement of said motor pulley toward said driven pulley to permit said motor pulley to slip with respect to said belt drive upon rotation of said motor in the other direction when the load upon said motor exceeds a predetermined value, a spring connected to said motor and support for urging said motor pulley into driving relation with said belt drive, said spring being tensioned to yield when said load exceeds said predetermined value, and spring means connected to said motor and having a friction member engageable with said support to prevent oscillation of said motor about the pivotal support when the motor pulley slips with respect to said belt drive.

3. In combination, a reversible motor having a drive pulley, means driven by said motor including a driven pulley, a belt drive between said pulleys, means for pivotally supporting said motor whereby the axis of the rotor for said motor is disposed laterally of a line extending between said pivot means and the axis of rotation of said driven pulley to provide a positive driving relation between said drive pulley and belt in one direction of rotation of said rotor and to permit said motor pulley to slip with respect to said belt upon rotation of said rotor in the opposite direction when the load upon said motor exceeds a predetermined value, and means for urging said motor pulley into driving relation with said belt, said means being yieldable when said load exceeds said predetermined value.

4. In combination, a reversible motor having a drive pulley, means driven by said motor including a driven pulley, a belt drive between said pulleys, means oiTset laterally from a line extending between the motor axis and the axis of rotation of said driven pulley for pivotally supporting said motor, and preloaded yieldable means for urging said drive pulley into driving relation with said belt, the preloading of said yieldable means being such that the drive pulley is moved toward the driven pulley to permit belt slippage when said motor is rotated in one direction and the load thereon exceeds the amount of said preloading, said preloading of said yieldable means also being such that when said motor is rotated in a reverse direction under load in the amount of said preloading a positive non-slipping driving relation is efiected between the drive pulley and belt but to permit belt slippage when the load on said motor considerably exceeds the amount of said preloading.

5. In combination, a reversible motor mounted for rotation about a vertical axis and having a drive pulley. means driven by said motor including a driven pulley, a belt drive between said pulleys, a support for said motor mounted to pivot about a vertical axis whereby the vertical axis of said motor is disposed laterally of a line extending between said vertical pivot axis and the axis of rotation of said driven pulley, and preloaded resilient means for urging said motor pulley into driving relation with said belt, said pivotal mounting and loading means acting to provide a positive driving relation between said 1 1 drive pulley and belt in one direction of rotation of said motor and to permit said drive pulley to slip with respect to said belt upon rotation of the motor in the opposite direction when the load upon said motor exceeds a predetermined value, said preloaded means being yieldable when the load exceeds said predetermined value to permit said motor to move in the direction of said driven pulley.

THOMAS R. SMITH.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date Lombard Feb. 25, 1930 Kindl et al. Mar. 9, 1937 Anderson May 28, 1940 Kirby Mar. 14, 1944 Hays, Jr Oct. 31, 1944 Bowen Jan. 21, 1947 Lund Apr. 6, 1948 

